Wilkes’ attorney said one witness the jurors never heard from might have changed their minds. Michael Williams, who said he managed the Panama Project for Wilkes, was set to testify that there was no bribery. He was prepared to bat down the assertions that Wilkes’ company performed shoddy work, submitted fraudulent invoices and schemed to sell overpriced computer hardware rather than continue scanning duties.

But when prosecutors and the judge declined to give Williams immunity, he decided not to risk incriminating himself by testifying.

Charlick said the court should have evened the playing field by giving him immunity, which is allowed under a previous 9th Circuit decision in an unrelated case, and let the jury conclude who was most credible.

“This is a complicated public corruption case,” she told the judges. “The impressions, the perceptions about why my client did this were incredibly relevant, and Combs and Wade presented their impressions.”

Assistant U.S. Attorney Phillip Halpern argued that Williams wasn’t even in a position to know much about the bribery or fraud activities, and that even if he would have testified, it might have hurt more than helped Wilkes in the long run.

“If they put that witness on the stand he would’ve been ripped to shreds,” Halpern said. “I think frankly it would’ve been worse.”

This is the second time the 9th Circuit is looking at this argument. In 2011, it ordered a hearing before Burns to explore the potential impact of Williams’ testimony. Afterward, Burns ruled that while the employee’s testimony largely corroborates Wilkes’, it was still minor in the grand scheme of the case and spoke more of background information rather than the charges directly.

The 9th Circuit panel on Monday seemed to be thinking along the same lines, saying they struggled to see how Williams directly contradicted the testimony of Combs and Wade.

In a separate argument, Wilkes is also appealing Burns’ denial of a new trial, in light of statements from Cunningham that deny the bribery, as well as lawsuits that suggest Wilkes’ $525,000 check was lost to a Ponzi scheme rather than a bribe.

(Cunningham pleaded guilty to conspiracy to commit bribery, mail fraud, wire fraud and tax evasion in 2005. He is believed to be living in Arkansas near family.)

Thirdly, Wilkes is also fighting a $636,000 forfeiture order. Burns set the amount when a jury declined to do so, but Wilkes’ attorney contends that is not legal.

At one point during the hearing, Judge Paul Watford asked how it came to be that Wilkes was still out of custody, six years after sentencing.

"It's unfortunate. ... We're talking about the largest congressional bribery case in history. I’m asked all the time, ‘It's how many years and the guy’s not in jail?'" Halpern said. "I don’t like that and it’s unfortunate.”